Gibbons display vocal skills similar to those of humans

Nature : Researchers in Japan, who have been conducting acoustic experiments on gibbons, have found that the animals have mastered some of the same vocal techniques that human opera singers use. Takeshi Nishimura of Kyoto University’s Primate Research Institute and colleagues used a helium-enriched environment to record the gibbons’ distinctive call. Helium is well known for the way it changes the pitch of the human voice. The researchers used helium’s unique properties to separate the contributions of the animals’ vocal folds from those of their vocal tracts. “Like professional sopranos, gibbons tune the resonant frequency of their vocal tract to the pitch frequency generated by the vocal folds to amplify the sound,” writes Kathryn Lougheed for Nature. Because the gibbons’ vocal mechanics appear to be physiologically similar to humans’, the finding dispels some long-held beliefs concerning human speech.